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On May 20, Washington Nationals center fielder Denard Span stepped to the plate against Cincinnati Reds ace Johnny Cueto in the third inning. Washington trailed 1-0 but had a runner on first base with one out. Span dropped a bunt down the third-base line, and when Ramon Santiago's rushed throw sailed into right field, Doug Fister came around to score and Span found himself at third.

Span scored on Anthony Rendon's sacrifice fly, and Washington went on to win 9-4, scoring six runs off Cueto, who came into the game with a 1.25 ERA. Span's bunt and the havoc it wrought were key to the victory.

Entering the week, Span had bunted five times in 2014, all in traditional sacrifice situations, and had reached base on three of those attempts. Win Probability Added (WPA) is a measure of the change in the likelihood of a batter's team winning a game from before his plate appearance to after it. Span's cumulative WPA when bunting in 2014 is 0.56, far higher than any other National League hitter. This means Span's five bunts have produced more than half a win for the Nationals. Driven by Span's success, the Nationals have a 0.54 WPA on bunts and are one of three teams with positive results.

In contrast to the Nationals, the Reds have made the poorest use of the bunt this season. Coming into the week, Cincinnati's 60 bunts were second most in the NL, after the Milwaukee Brewers' 63. The Reds' cumulative WPA on those bunts was minus 0.83, meaning their average bunt cost the team more than 1% of win probability.

Cueto has been one of the primary culprits, failing to reach base on any of his 10 bunt attempts, including two in non-sacrifice situations, costing the Reds 0.23 points of WPA. Not surprisingly, Cincinnati's most frequent bunter has been Billy Hamilton, who has balanced five bunt singles with 11 failures to reach base or move a runner. Hamilton's 19 bunts (including three sacrifices) have yielded a WPA of minus 0.12.

Cueto's struggles while bunting are not uncharacteristic of pitchers. NL pitchers have dropped 273 bunts, or 43% of all NL attempts, and have averaged minus 0.020 points of WPA on each attempt, compared with an average WPA of minus 0.011 in all plate appearances. NL position players have averaged 0.04 WPA when bunting, far better than their average WPA in all plate appearances, which is about a hundredth of a percent less than zero.

Span's WPA in all plate appearances this season is 1.78, ninth in the NL. His five bunts have averaged an improvement in win probability of about 11%, while his non-bunts have averaged less than 1%.

Should Span try bunting more? Maybe. While Span's speed gives him an advantage when bunting, Hamilton and the Los Angeles Dodgers' Dee Gordon — speedsters and leaders in bunt attempts in 2014 — have had considerably less success, both accumulating negative WPA. This suggests a conservative approach to bunting might be just as advantageous as speed or soft hands. The San Francisco Giants have attempted fewer bunts (28) than any other NL team and have had more success (0.34 WPA) than any team except Washington.

Players such as Span have made excellent use of the bunt in 2014, while pitchers and other frequent bunters have had less success. The element of surprise just might be a bunter's best friend.

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BEST AND WORST

Highest WPA in NL

Highest WPA in NL on bunts

PA through Friday, according to Fangraphs.com

Rk. Player

Team

WPA

Rk. Player

Team

WPA

1. Denard Span

Nationals

0.56

1. Giancarlo Stanton

Marlins

3.28

2. Jean Machi

Giants

0.32

2. Neil Walker

Pirates

2.45

3. Carlos Gomez

Brewers

0.24

3. Michael Morse

Giants

2.23

4. Christian Yelich

Marlins

0.22

4. Yasiel Puig

Dodgers

2.14

5. Neil Walker

Pirates

0.21

5. Hunter Pence

Giants

2.11

T-6. Danny Espinosa

Nationals

0.17

6. Nolan Arenado

Rockies

1.97

T-6. Anthony Recker

Mets

0.17

7. Troy Tulowitzki

Rockies

1.81

8. Ben Revere

Phillies

0.16

8. Justin Morneau

Rockies

1.79

9. Darwin Barney

Cubs

0.15

T-9. Denard Span

Nationals

1.78

10. Marcell Ozuna

Marlins

0.13

T-9. Casey McGehee

Marlins

1.78

Lowest WPA in NL

Lowest WPA in NL on bunts

PA through Friday, according to Fangraphs.com

Rk. Player

Team

WPA

Rk. Player

Team

WPA

1. Tim Federowicz

Dodgers

-0.32

1. Jordy Mercer

Pirates

-1.76

2. Ryan Kalish

Cubs

-0.26

2. Zack Cozart

Reds

-1.63

3. Jeff Samardzija

Cubs

-0.23

3. Jedd Gyorko

Padres

-1.62

4. Johnny Cueto

Reds

-0.23

4. Nate Schierholtz

Cubs

-1.27

5. Marco Estrada

Brewers

-0.22

5. Travis dArnaud

Mets

-1.2

Most bunts attempted

Fewest bunts attempted

1. Milwaukee

63

1. San Francisco

28

2. Cincinnati

60

2. Arizona

30

T-3. Chicago

49

3. Atlanta

31

T-3. Miami

49

4. San Diego

35

5. Los Angeles

48

T-5. Colorado

37

T-5. Philadelphia

37

Highest team WPA on bunts

Lowest team WPA on bunts

1. Washington

0.54

1. Cincinnati

-0.83

2. San Francisco

0.34

2. Chicago

-0.74

3. Colorado

0.04

3. Los Angeles

-0.71

4. New York

0.01

4. Atlanta

-0.67

5. St. Louis

-0.01

5. Pittsburgh

-0.63

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